1. Field of the Invention
The present invention relates to a pump system including a plurality of hydraulic pump bodies, and a pump unit having a cooling fan unit.
2. Related Art
Conventionally, a pump unit has been widely used in a traveling power transmission mechanism in a working vehicle or the like. The pump unit includes a single input shaft, a plurality of pump shafts operatively connected to the input shaft, a plurality of hydraulic pump bodies respectively driven by the plurality of pump shafts, a pump case for accommodating the plurality of hydraulic pump bodies and supporting the input shaft and the plurality of pump shafts, and a port block connected to the pump case (see, for example, JP-A 2003-291674).
In the conventional pump unit, the input shaft can be operatively connected to a driving source through a power transmission mechanism such as a pulley with the pump case connected to a support member such as a vehicle frame, and the plurality of hydraulic pump bodies can be driven through a single input path.
However, the conventional pump unit has a room for improvement in workability in replacing or maintaining the hydraulic pump bodies.
In other words, in the conventional pump unit, the pump case is connected to the support member such as the vehicle frame.
Therefore, for replacing or maintaining the hydraulic pump bodies, it is necessary to separate the whole pump unit including the input shaft from the support member or to separate the port block from the pump case.
In the former method, it is necessary to release an engagement between the input shaft and the power transmission mechanism from each other. In the latter method, it is necessary to separate the port block from the pump case with the pump case connected to the support member such as the vehicle frame. Therefore, workability is poor and constituent parts of the hydraulic pump bodies may be unintentionally detached.
Although the pump unit may be provided with a charge pump body and a cooling fan body in some cases depending on specifications, there is no pump unit to which those members can easily and conveniently be attached.
The present invention has been accomplished in view of the aforementioned conventional art and it is an object of the present invention to provide a pump system in which efficiency of replacement and maintenance operation of the hydraulic pump bodies can be increased.
It is another object of the present invention to provide a pump unit to/from which a cooling fan and/or a charge pump can be easily attached/detached.